scholarly journals Contribution to the ongoing discussion on fluoride toxicity

2021 ◽  
Author(s):  
Sabine Guth ◽  
Stephanie Hüser ◽  
Angelika Roth ◽  
Gisela Degen ◽  
Patrick Diel ◽  
...  
Keyword(s):  
Epidemiological Studies ◽  
Confounding Factors ◽  
Inclusion Criteria ◽  
Fluoride Toxicity ◽  
If Current ◽  
Exposure Levels ◽  
Positive Results ◽  
Current Exposure ◽  
Totality Of Evidence

AbstractSince the addition of fluoride to drinking water in the 1940s, there have been frequent and sometimes heated discussions regarding its benefits and risks. In a recently published review, we addressed the question if current exposure levels in Europe represent a risk to human health. This review was discussed in an editorial asking why we did not calculate benchmark doses (BMD) of fluoride neurotoxicity for humans. Here, we address the question, why it is problematic to calculate BMDs based on the currently available data. Briefly, the conclusions of the available studies are not homogeneous, reporting negative as well as positive results; moreover, the positive studies lack control of confounding factors such as the influence of well-known neurotoxicants. We also discuss the limitations of several further epidemiological studies that did not meet the inclusion criteria of our review. Finally, it is important to not only focus on epidemiological studies. Rather, risk analysis should consider all available data, including epidemiological, animal, as well as in vitro studies. Despite remaining uncertainties, the totality of evidence does not support the notion that fluoride should be considered a human developmental neurotoxicant at current exposure levels in European countries.

Adverse Effects of Natural Products: A Brief Pre-Systematic Review

2020 ◽  
Vol 01 ◽  
Author(s):  
Carla Pires ◽  
Ana Fernandes
Keyword(s):  
Systematic Review ◽  
Adverse Event ◽  
Natural Products ◽  
Adverse Events ◽  
In Vitro Study ◽  
Google Scholar ◽  
Inclusion Criteria ◽  
Exclusion Criteria ◽  
Meta Analyses

Background: Natural products are commonly used for treating health problems. These products may be associated with adverse events, which are defined as "noxious and unintended response to a medicinal product" by the European Medicine Agency. Objectives: To identify studies describing at least one adverse event (or with potential to promote an adverse event) related to the use of natural products, as well as to describe the involved product(s) and adverse event(s). Methods: A pre-systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria. Keywords: "natural product(s)" and ["adverse drug reaction(s)" or "adverse effect(s)"]. Screened databases: PubMed, SciELO, DOAJ and Google Scholar. Inclusion criteria: papers describing at least one adverse event associated with the use of natural products and published between 2017 and 2019. Exclusion criteria: Repeated studies, reviews and papers written in other languages than English, Portuguese, French or Spanish. Results: 104 studies were identified (20 PubMed; 0 SciELO; 2 DOAJ; 82 Google Scholar), but only 10 were selected (4 PubMed and 6 Google Scholar): 1 in-vitro study; 2 non-clinical studies, 1 study reporting in-vitro and clinical data and 5 studies were cases reports. Globally, 997 reports of adverse drug reactions with natural products were identified, mainly non-severe cases. Conclusion: Since a limited number of studies was found, we conclude that adverse events due to natural products may be underreported, or natural products may have a good safety profile. This review contributes for assuring the safety of natural products consumers, by evaluating the knowledge/information on the potential adverse events and interactions of these products.

scholarly journals TO010A NEW IMMUN-TOXICOLOGICAL TEST TO DETECT POLYSULFONE HYPERSENSITIVITY IN HEMODIALYSIS PATIENTS

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Joachim Beige ◽  
Ralph Wendt ◽  
Despina Rüssmann ◽  
Karl-Peter Ringel
Keyword(s):  
False Negative ◽  
False Negative Rate ◽  
Lymphocyte Transformation ◽  
Clinical Problem ◽  
Lymphocyte Transformation Test ◽  
Laboratory Research ◽  
Humoral Immune ◽  
Before And After ◽  
Positive Results

Abstract Background and Aims Incompatibility of dialysis procedure due to hypersensitivity against dialyzer material which currently is mainly based on polysulfone and derivatives can not be assessed by routine laboratory tests. Although the frequency of such symptoms is suspected to be low (below 2%) such resembles an important clinical problem because dialysis procedures are frequently accompanied by symptoms of non-tolerability with reasons not being entirely clear while circulatory reasons are suspected to play a major role. Method To enlighten the role of polysulfone hypersensitivity, we adapted known standardized material immune-toxicological tests (lymphocyte transformation test, basophil degranulation test) to the specific conditions of dialysis and polysulfone material sensitivity. We developed a method of polysulfone micronisation and measured humoral immune response of isolated patient´s lymphocytes when incubated with polysulfone dispersion. Results 39 samples from 103 patients with suspected polysulfone hypersensitivity showed positive results for type 1 (n=19), type 4 (n=18) or both type (n=2) reactions. There were no significant differences in the level of stimulation measured for DI, SI and lymphogenesis before and after dialysis (average delta -0.4; -0.28; - 1.74, p = 0.71; 0.34; 0.37) and with different dialyzer materials (Tab. 1). Patients with pos. type 4 results (LTT and lymphogenesis) showed highly correlated results in either LTT or lymphogenesis test (Fig. 1, R=0.87, p<0.0001). 8 out of 8 samples from patients with repeated test on different PS showed positive results on either PS. One patient tested positive on PS showed no hypersensitivity with another non-PS (PMMA) material. Conclusion This is the first methodological report showing plausible in-vitro results of patients samples concerning polysulfone intolerance. On the first superficial view, a “false-negative” rate of 60% looks rather disappointing, because all samples derived from patients with suspicion of PS hypersensitivity. However, due to the clinical variability of intolerance symptoms and the high prevalence of any problems after HD initiation, mainly of circulatory origin after initiating extracorporeal circuit, this rate may obviously express the true frequency of isolated PS material hypersensitivity in suspected patients. Alternative pathophysiological pathways of material sensitivity like complement activation, remain to be elucidated and incorporated into a comprehensive future testing panel. Further clinical and laboratory research is needed to define true polysulfone hypersensitivity and to enlighten the field of hypothetic subclinical material incompatibility in patients with impaired dialysis tolerability.

A Study on UV Filter Chemicals from Annex VII of European Union Directive 76/768/EEC, in the In Vitro 3T3 NRU Phototoxicity Test

1998 ◽  
Vol 26 (5) ◽  
pp. 679-708 ◽  
Author(s):  
Horst Spielmann ◽  
Michael Balls ◽  
Jack Dupuis ◽  
Wolfgang J. W. Pape ◽  
Odile de Silva ◽  
...  
Keyword(s):  
Neutral Red ◽  
Optimum Concentration ◽  
Alternative Methods ◽  
Uv Filter ◽  
Eu Directive ◽  
Optimum Concentration Range ◽  
The Impact ◽  
Positive Results

In 1996, the Scientific Committee on Cosmetology of DGXXIV of the European Commission asked the European Centre for the Validation of Alternative Methods to test eight UV filter chemicals from the 1995 edition of Annex VII of Directive 76/768/EEC in a blind trial in the in vitro 3T3 cell neutral red uptake phototoxicity (3T3 NRU PT) test, which had been scientifically validated between 1992 and 1996. Since all the UV filter chemicals on the positive list of EU Directive 76/768/EEC have been shown not to be phototoxic in vivo in humans under use conditions, only negative effects would be expected in the 3T3 NRU PT test. To balance the number of positive and negative chemicals, ten phototoxic and ten non-phototoxic chemicals were tested under blind conditions in four laboratories. Moreover, to assess the optimum concentration range for testing, information was provided on appropriate solvents and on the solubility of the coded chemicals. In this study, the phototoxic potential of test chemicals was evaluated in a prediction model in which either the Photoirritation Factor (PIF) or the Mean Photo Effect (MPE) were determined. The results obtained with both PIF and MPE were highly reproducible in the four laboratories, and the correlation between in vitro and in vivo data was almost perfect. All the phototoxic test chemicals provided a positive result at concentrations of 1μg/ml, while nine of the ten non-phototoxic chemicals gave clear negative results, even at the highest test concentrations. One of the UV filter chemicals gave positive results in three of the four laboratories only at concentrations greater than 100μg/ml; the other laboratory correctly identified all 20 of the test chemicals. An analysis of the impact that exposure concentrations had on the performance of the test revealed that the optimum concentration range in the 3T3 NRU PT test for determining the phototoxic potential of chemicals is between 0.1μg/ml and 10μg/ml, and that false positive results can be obtained at concentrations greater than 100μg/ml. Therefore, the positive results obtained with some of the UV filter chemicals only at concentrations greater than 100μg/ml do not indicate a phototoxic potential in vivo. When this information was taken into account during calculation of the overall predictivity of the 3T3 NRU PT test in the present study, an almost perfect correlation of in vitro versus in vivo results was obtained (between 95% and 100%), when either PIF or MPE were used to predict the phototoxic potential. The management team and participants therefore conclude that the 3T3 NRU PT test is a valid test for correctly assessing the phototoxic potential of UV filter chemicals, if the defined concentration limits are taken into account.

scholarly journals Antidiabetic Properties of Naringenin: A Citrus Fruit Polyphenol

Biomolecules ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 99 ◽  
Author(s):  
Danja J. Den Hartogh ◽  
Evangelia Tsiani
Keyword(s):  
Insulin Resistance ◽  
Animal Studies ◽  
Citrus Fruit ◽  
Epidemiological Studies ◽  
Personal Health ◽  
Current Review ◽  
Vegetables And Fruits

Type 2 diabetes mellitus (T2DM) is a metabolic disease characterized by insulin resistance and hyperglycemia and is associated with personal health and global economic burdens. Current strategies/approaches of insulin resistance and T2DM prevention and treatment are lacking in efficacy resulting in the need for new preventative and targeted therapies. In recent years, epidemiological studies have suggested that diets rich in vegetables and fruits are associated with health benefits including protection against insulin resistance and T2DM. Naringenin, a citrus flavanone, has been reported to have antioxidant, anti-inflammatory, hepatoprotective, nephroprotective, immunomodulatory and antidiabetic properties. The current review summarizes the existing in vitro and in vivo animal studies examining the anti-diabetic effects of naringenin.

scholarly journals Antagonistic activity of endophytic bacteria isolated from weed plant against stem end rot pathogen of pitaya in Vietnam

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
The Anh Luu ◽  
Quyet Tien Phi ◽  
Thi Thu Hang Nguyen ◽  
Mai Van Dinh ◽  
Bich Ngoc Pham ◽  
...  
Keyword(s):  
Endophytic Bacteria ◽  
Indole Acetic Acid ◽  
Pathogenic Fungi ◽  
Antagonistic Activity ◽  
Biofilm Production ◽  
Weed Plant ◽  
Seedling Biomass ◽  
Rot Disease ◽  
Positive Results

Abstract Background Fungal stem end rot disease of pitaya caused by Alternaria alternata is one of the most destructive diseases in Binh Thuan province, Vietnam. This study aimed to assess the antagonistic effects of some endophytic bacteria isolated from the weed plant (Echinochloa colonum) against A. alternata. Results A total of 19 endophytic bacteria were isolated and 5 of them presented in vitro antagonistic activity against A. alternata. Of five, strain EC80 significantly inhibited the pathogenic growth with a mean inhibition diameter of 11.88 ± 0.08 mm, while the other four (C79, EC83, EC90, and EC97) showed a weak inhibition. Interestingly, the combination of EC79 and EC80 reduced more biomass of pathogenic fungi than the single one did. EC79 showed positive results for amylase, indole acetic acid (IAA), and biofilm production, whereas EC80 presented positive capabilities for IAA and biofilm production and a negative one for amylase production. In addition, the combined filtrate of EC79 and EC80 presented non-antifungal activity on biocontrol tests in vitro, indicating that bacteria cells played a role in defending against the pathogen. Moreover, both isolates EC79 and EC80 significantly increased seedling biomass than the control. Conclusions The results suggest that those two strains in combination had the potential to be used as a biocontrol agent against A. alternata. More studies should be done in the future to evaluate their efficiency under the field conditions.

scholarly journals Loss of Nitric Oxide Induces Fibrogenic Response in Organotypic 3D Co-Culture of Mammary Epithelia and Fibroblasts—An Indicator for Breast Carcinogenesis

Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2815
Author(s):  
Gang Ren ◽  
Xunzhen Zheng ◽  
Vandana Sharma ◽  
Joshua Letson ◽  
Andrea L. Nestor-Kalinoski ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Culture System ◽  
Epithelial Mesenchymal Transition ◽  
Precancerous Lesions ◽  
Three Dimensional ◽  
Epidemiological Studies ◽  
Mesenchymal Transition ◽  
In Vitro Response ◽  
Mammary Epithelia

Excessive myofibroblast activation, which leads to dysregulated collagen deposition and the stiffening of the extracellular matrix (ECM), plays pivotal roles in cancer initiation and progression. Cumulative evidence attests to the cancer-causing effects of a number of fibrogenic factors found in the environment, diseases and drugs. While identifying such factors largely depends on epidemiological studies, it would be of great importance to develop a robust in vitro method to demonstrate the causal relationship between fibrosis and cancer. Here, we tested whether our recently developed organotypic three-dimensional (3D) co-culture would be suitable for that purpose. This co-culture system utilizes the discontinuous ECM to separately culture mammary epithelia and fibroblasts in the discrete matrices to model the complexity of the mammary gland. We observed that pharmaceutical deprivation of nitric oxide (NO) in 3D co-cultures induced myofibroblast differentiation of the stroma as well as the occurrence of epithelial–mesenchymal transition (EMT) of the parenchyma. Such in vitro response to NO deprivation was unique to co-cultures and closely mimicked the phenotype of NO-depleted mammary glands exhibiting stromal desmoplasia and precancerous lesions undergoing EMT. These results suggest that this novel 3D co-culture system could be utilized in the deep mechanistic studies of the linkage between fibrosis and cancer.

scholarly journals Glycemic Index of Gluten-Free Bread and Their Main Ingredients: A Systematic Review and Meta-Analysis

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 506
Author(s):  
Bernardo Romão ◽  
Ana Luísa Falcomer ◽  
Gabriela Palos ◽  
Sandra Cavalcante ◽  
Raquel Braz Assunção Botelho ◽  
...  
Keyword(s):  
Systematic Review ◽  
Glycemic Index ◽  
Resistant Starch ◽  
Web Of Science ◽  
Meta Analysis ◽  
Gluten Free ◽  
Inclusion Criteria ◽  
Glycemic Profile

This study aimed to perform a systematic review and meta-analysis of the glycemic index (GI) of gluten-free bread (GFB) and its main ingredients. The systematic review followed PRISMA guidelines, using seven electronic databases (PubMed, EMBASE, Scopus, Science Direct, Web of Science, gray literature research with Google Scholar, and patents with Google Patent tool), from inception to November 2020. Eighteen studies met the inclusion criteria evaluating 132 GFB samples. Five articles tested GI in vivo, eleven in vitro; and two studies tested both methods. The analysis showed that 60.7% (95% CI: 40.2–78.1%) of the samples presented high glycemic indexes, evidencing a high glycemic profile for GFB. Only 18.2% (95% CI: 11.7–27.2%) of the bread samples presented in the studies were classified as a low GI. Meta-analysis presented moderate/low heterogenicity between studies (I2 = 61% and <1% for both high and low GIs) and reinforced the proportion of high GIs. Lower GIs were found in formulations based on Colocasia esculenta flour or enriched with fiber, yogurt and curd cheese, sourdough, psyllium, hydrocolloids, enzymes, fructans, and resistant starch, highlighting the efficacy of these ingredients to lower GFBs’ GI. GFB tends to present high GI, impacting the development of chronic diseases when consumed.

scholarly journals Screening for Tuberculosis in Health Care Workers: Experience in an Italian Teaching Hospital

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Christian Napoli ◽  
Filippo Ferretti ◽  
Filippo Di Ninno ◽  
Riccardo Orioli ◽  
Alessandra Marani ◽  
...  
Keyword(s):  
Health Care ◽  
Teaching Hospital ◽  
Health Care Workers ◽  
Screening Tests ◽  
Specificity And Sensitivity ◽  
Large Teaching Hospital ◽  
Care Workers ◽  
Low Incidence ◽  
Positive Results

Health care workers (HCW) are particularly at risk of acquiring tuberculosis (TB), even in countries with low TB incidence. Therefore, TB screening in HCW is a useful prevention strategy in countries with both low and high TB incidence. Tuberculin skin test (TST) is widely used although it suffers of low specificity; on the contrary, the in vitro enzyme immunoassay tests (IGRA) show superior specificity and sensitivity but are more expensive. The present study reports the results of a three-year TB surveillance among HCW in a large teaching hospital in Rome, using TST (by standard Mantoux technique) and IGRA (by QuantiFERON-TB) as first- and second-level screening tests, respectively. Out of 2290 HCW enrolled, 141 (6.1%) had a positive TST; among them, 99 (70.2%) underwent the IGRA and 16 tested positive (16.1%). The frequency of HCW tested positive for TB seems not far from other experiences in low incidence countries. Our results confirm the higher specificity of IGRA, but, due to its higher cost, TST can be considered a good first level screening test, whose positive results should be further confirmed by IGRA before the patients undergo X-ray diagnosis and/or chemotherapy.

High Rate of Negative Results of Tuberculin and QuantiFERON Tests Among Individuals With a History of Positive Skin Test Results

2006 ◽  
Vol 27 (5) ◽  
pp. 436-441 ◽  
Author(s):  
Lloyd N. Friedman ◽  
Esther R. Nash ◽  
June Bryant ◽  
Susan Henry ◽  
Julia Shi ◽  
...  
Keyword(s):  
Skin Test ◽  
Significant Proportion ◽  
High Rate ◽  
Negative Group ◽  
Tuberculosis Screening ◽  
Positive Skin ◽  
Screening Programs ◽  
History Of ◽  
Positive Results

Objectives.To evaluate individuals at high risk for tuberculosis exposure who had a history of a positive tuberculin skin test (TST) result in order to determine the prevalence of unsuspected negative TST results. To confirm these findings with the QuantiFERON-TB test (QFT), an in vitro whole-blood assay that measures tuberculin-induced secretion of interferon-γ.Methods.This survey was conducted from November 2001 through December 2003 at 3 sites where TST screening is regularly done. Detailed histories and reviews of medical records were performed. TSTs were placed and read by 2 experienced healthcare workers, and blood was drawn for QFT. Any subject with a negative result of an initial TST during the study (induration diameter, <10 mm) underwent a second TST and a second QFT. The TST-negative group comprised individuals for whom both TSTs had an induration diameter of <10 mm. The confirmed-negative group comprised individuals for whom both TSTs yielded no detectable induration and results of both QFTs were negative.Results.A total of 67 immunocompetent subjects with positive results of a previous TST were enrolled in the study. Of 56 subjects who completed the TST protocol, 25 (44.6%; 95% confidence interval [CI], 31.6%-57.6%) were TST negative (P<.001). Of 31 subjects who completed the TST protocol and the QFT protocol, 8 (25.8%; 95% CI, 10.4%-41.2%) were confirmed negative (P<.005).Conclusions.A significant proportion of subjects with positive results of a previous TST were TST negative in this study, and a subset of these were confirmed negative. These individuals' TST status may have reverted or may never have been positive. It will be important in future studies to determine whether such individuals lack immunity to tuberculosis and whether they should be considered for reentry into tuberculosis screening programs.

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